Friday, February 27, 2015

Descartes’ “indivisibility” argument

[T]here is a vast difference between
mind and body, in respect that body, from its nature, is always divisible, and
that mind is entirely indivisible. For
in truth, when I consider the mind, that is, when I consider myself in so far
only as I am a thinking thing, I can distinguish in myself no parts, but I very
clearly discern that I am somewhat absolutely one and entire; and although the
whole mind seems to be united to the whole body, yet, when a foot, an arm, or
any other part is cut off, I am conscious that nothing has been taken from my
mind; nor can the faculties of willing, perceiving, conceiving, etc., properly
be called its parts, for it is the same mind that is exercised [all entire] in
willing, in perceiving, and in conceiving, etc. But quite the opposite holds in corporeal or
extended things; for I cannot imagine any one of them [how small soever it may
be], which I cannot easily sunder in thought, and which, therefore, I do not
know to be divisible. This would be
sufficient to teach me that the mind or soul of man is entirely different from
the body, if I had not already been apprised of it on other grounds.

This is
Descartes’ “indivisibility argument” for dualism. As with many of Descartes’ other arguments, I
think both that it is not compelling as it stands, but also that it is much
more interesting than it is often given credit for. I devoted a few pages to the argument in Philosophy
of Mind. I won’t repeat here
everything I said there.

As Dale Jacquette
interprets Descartes in his own book Philosophy
of Mind, the argument can be summarized as follows:

1. My body is divisible into like
parts (bodies)

2. My mind is not divisible into like
parts (minds)

3. My body ≠
my mind

Jacquette’s
reason for speaking of divisibility “into like
parts” is that Descartes does not deny that we can distinguish different
faculties within the mind, such as willing, perceiving, and conceiving. What Descartes denies (on Jacquette’s
reading) is that the mind can be divided into parts which are themselves minds. The
idea would be that you cannot divide a mind into parts that are like what you
started out with (two or more minds), whereas you can divide a material object into
parts that are like what you started out with (two or more material
objects). So, material things have a
property that minds lack, viz. divisibility into like parts. And thus, by Leibniz’s Law,
the mind cannot be identified with a material thing.

Suppose we
accept Jacquette’s reading. What should
we think of the argument? It might seem
at first glance that the argument fails with the first premise. For isn’t it simply false to say of material
things in general that they are
divisible into like parts? To be sure,
if you divide a stone in half, you get two stones, and if you divide a piece of
wood you get two pieces of wood. But if
you divide a human body in half, you do not get two human bodies; if you divide
a car, you don’t get two cars; if you divide a circular object, you don’t get
two circles; and so forth. Indeed, even
with stone and wood, if you keep dividing them you’ll eventually get to
something that isn’t stone or wood.

But this
objection is too quick. Since Descartes
was obviously aware of these facts, he cannot have meant that if you divide a
human body you’ll get two human bodies, etc.
So what does he mean? Recall that
for Descartes, the essence of matter is to be extended in space. Matter just
is extension, and nothing but extension.
Thus when he says that body is divisible into like parts, what he means,
no doubt, is that if you divide an extended thing the result will be two or
more things that are also extended. They
may not be human bodies,
specifically, or cars, or what have you, but they will be extended. So, given
Descartes’ conception of matter, it is certainly understandable why he would
take the first premise to be true.

We’ll come
back to that, but let’s turn for the moment to the second premise. If for Descartes the essence of matter is
extension, the mind is, on his view, essentially that which thinks to itself: I think, therefore I am. It is the “I,” the ego, the self which
remains in Meditation II after everything else has been doubted away by the end
of Meditation I. When Descartes (as
Jacquette interprets him) says that the mind cannot be divided into like parts,
I would suggest that what he means is that you can’t break an “I” or ego down
into two or more “I’s” or egos, the way you can break an extended thing down
into two or more extended things.

Why does
Descartes think that the self or ego is indivisible in this way? Note first that Descartes says that “when a
foot, an arm, or any other part is cut off, I am conscious that nothing has
been taken from my mind.” He seems to be
alluding here to the argument of Meditation I to the effect that it could in
principle turn out that none of his “hands, eyes, flesh, blood [and] senses”
are real, insofar as his belief that his body exists could be a delusion
foisted upon him by an evil spirit. The
point, I take it, is not that his mind might in principle exist even if his
body did not; that would be the thrust of his
“clear and distinct perception” argument for dualism, and the
“indivisibility” argument is presumably supposed to be an independent argument
for dualism. The point in the present
context seems rather to be to give an example of something that might at first
glance appear to be a part of the self which on reflection is not really part
of the self at all. An arm might seem to
be a part of the “I” or ego, yet the “I” or ego can conceive of a situation in
which it turns out that the arm does not exist, and perhaps never existed but
was always only ever a hallucination, and yet where the “I” or ego nevertheless
exists all the same. Hence the arm isn’t
really a part of the “I” or ego, but at best just something contingently
attached to it. And of course, if
separated an arm certainly wouldn’t constitute another “I” or self all on its
own.

But couldn’t
there be a case of a mental (as
opposed to bodily) part of the self which, if it were to be lost, would
constitute another “I” or self that has split off? In particular, don’t the phenomena associated
with “dissociative identity disorder” and “split brain” patients provide
evidence that this can happen? As I
noted in Philosophy of Mind, the
significance of such phenomena has been greatly exaggerated. How to interpret these cases is a matter of
controversy, and in my view there is nothing going on in them that amounts to a
single mind splitting into two, but merely a single mind becoming severely
addled. But suppose for the sake of
argument that in some of these cases there really are two or more utterly
distinct minds where previously there seemed to be only one. Would Descartes have regarded this as a
refutation of his thesis?

I think
not. Suppose you found yourself in a
situation in which another mind suddenly seemed to be sharing control of your
body. Perhaps it would invade your
thoughts and you would consciously struggle with it for control, like Steve
Martin does with Lily Tomlin in the movie All of Me. Or perhaps it would completely take over
control for extended periods of time without your realizing what is going on,
as in (too-late spoiler alert!) Fight Club. Either way, I imagine Descartes would argue
as follows: You could easily conceive of being rid of this second mind or self and
carrying on “one and entire” without it, just as you can conceive of your “I”
or ego carrying on “one and entire” in the absence of your arm or foot. And in that case this other mind or self was
never really a part of the “I” or ego at all, any more than the arm or foot
was, but only something contingently associated with it. Even if it seemed that it had “split off” from you, this would be an
illusion. It could only ever have been
something contingently attached to you which you had belatedly become aware of,
like a barnacle on a ship that has been attached to it for weeks before it is
detected and scraped off. For if this
second self had ever really been a part of you, then you could not conceive of continuing “one and
entire” without it. You would instead be
conceiving of a case where you persist in a diminished or incomplete way in the
absence of this other mind or self. But
in fact what you are conceiving of is continuing in a complete way in the absence
of something alien which had for whatever
reason come to be attached to you. A
purported second “I” or ego which splits off from my “I” or ego is thus like
the body: I can conceive of existing without it, and thus it is not really a part of the original “I” or ego
at all.

If this is
correct, then Descartes’ argument might seem to go through. If the “I” or ego were a material (i.e.
extended) thing, then since from any material thing you can split off a part
that is itself a material thing, it should also be the case that you can split
off from the “I” or ego a part that is itself an “I” or ego. But that is not the case. So the “I” or ego is not a material thing.

But not so
fast. The argument is still problematic,
and, it seems to me, more because of what Descartes says about matter than because of what he says
about the “I” or ego. For one thing, the
argument seems to presuppose that matter is infinitely
divisible, that no matter how far down you go in dividing a material thing you will
always be able to divide the resulting parts further. And indeed, that is precisely what Descartes
thinks. But that is, needless to say, a highly
controversial assumption. Suppose a
critic opted instead for an atomist account of matter on which there is a
bottommost level of material bits which cannot be divided further, or a
corpuscularian theory on which there is a bottommost level that might in
principle be divided further but in fact is not so divided. Would that sink Descartes’ argument?

The
Cartesian might respond as follows: Even if there is such a level, it would not
help the materialist. For the materialist
wants to identify the self with some material object at the macro level -- in particular, with the
brain. And macro level objects like the
brain are in the relevant sense divisible into like parts. Hence the “I” or ego could not be identified
with any of them.

The trouble
with this reply, though, is that a materialist willing to think outside the box
could decide to identify the “I” or self with an atom or corpuscle. He could say: “I’m happy to think of the ego
or self, as Descartes does, as akin to a Leibnizian monad -- as simple,
undivided, or non-composite. But unlike Descartes
and Leibniz, I think it should nevertheless be identified with a material thing that is simple, undivided
or non-composite. It’s comparable to
what Leibniz would call the ‘dominant monad’ of a system. It’s the one atom or corpuscle in the human
body that is associated with thought, and governs all the other, unthinking
atoms or corpuscles that make up the body.”

Needless to
say, this materialist move would itself be problematic in several ways. Why would some atoms or corpuscles be associated
with thought while others are not? How
exactly does this one purportedly thinking material particle govern the rest? How
could there be any material thing, however minute, that is in principle indivisible
or non-composite?

But to
address such questions would be to go well beyond what Descartes has to say in
the indivisibility argument itself. So, because
such questions would need to be addressed -- and because I think Descartes’ own
conception of matter is just wrong -- I think the “indivisibility” argument as
it stands is not compelling. But that
doesn’t mean that there aren’t insights in it that couldn’t be developed into a
better argument. Indeed, we
Aristotelian-Thomists would certainly hold that there is a sense in which any material substance can be decomposed into component
parts (insofar as even the simplest or bottommost material substances are still
going to be composed of substantial form and prime matter). And Thomists also hold that there is a sense
in which the soul is simple or non-composite (though of course it does not have
the absolute simplicity that is
unique to God).

But spelling
all this out would take us far from anything distinctively Cartesian. And that is no surprise. As I have noted in earlier posts (here,
here,
and here)
what is of abiding value in Descartes’ arguments typically turns out to be the
elements he borrowed from the Scholastic tradition that preceded him rather than
the novelties he introduces.

52 comments:

Chisholm had a slightly more interesting take on this argument based on his Mereological Essentialism and account of persistence over time. Not that the Scholastic will have any truck with Mereological Essentialism of course.

One should point out that the monadology is essentially a theosophy since it starts with the notion of God, an Infinite and Necessary Being. The monad then, which is a contingent being, is ontologically an infinitesimal. any existential subject (a compound/material substance) is synthesized via its substantial form (essential/simple subjectivity) which is monadological. so, you are a monad, your heart is a monad, your brain is a monad, atoms are monads, electrons are monads etc.

At least it has always seemed clear to me that Leibniz is a theosophist in his method as he always starts with the Being and arrives at the beings. Likewise, its implied that he believes matter to be 'gunk' (I believe this is the term some analytics use) or that reality is purely formal and ultimately immaterial. This should mean that mechanical models are predicated to natural processes analogically; that probabilities and 'indeterminacy' are psychologically subjective. What this means for free will is that ultimately the human subject is only present to God and in God; that the choices he makes generate worlds and yet this does not entail that the other monads are illusions due to the harmony of monads, the relation between infinite and finite being, etc. I'm sure one can easily grasp the rest in more detail. the end result is a grand psychological-cosmological occasionalism; the individual subject is the occasion for a world.

Is it true that one's mind cannot be divided, that one cannot be "of two minds"? I'm reminded of Paul in Romans 7 and James in James 1:5–8, as well as Emil Brunner's Man in Revolt, which should really have been translated as Man in Contradiction; the original German title Der Mensch im Widerspruch captures both the (i) revolt and (ii) contradiction aspects.

Once a mind has embraced a logical contradiction, might that split it into two parts? One part asserts one side of the contradiction, while the other asserts the other side. There is no need for knowledge of this contradiction to be conscious, or at least to stay conscious. See Eric Schwitzgebel's The Unreliability of Naive Introspection and Josef Pieper's The Concept of Sin.

It strikes me that we should examine the possibility of joining once-sundered minds, perhaps along the lines of Eph 2:11–22, not to mention Eph 4:1–16. Furthermore, we could explore the discussion of "heart" in Jeremiah, and the criticism he had that the Israelites had multiple hearts and were driving apart from one another. With this in mind, Paul's note that "But we have the mind of Christ." at the end of 1 Cor 2:14–16 might take on new significance.

"But if you divide a human body in half, you do not get two human bodies; "

This seems potentially problematic.

If I were to be cut in twain, the two bodies consequently produced would still be human. Consider forensics. Finding the bones or even just the teeth suffices to have found, in many cases, "the body" simply. But how do we know? Because we found human bones or specifically human teeth; and not only that, but exactly this (human) person's teeth. There is a something that makes the bodies not only properly human but even properly this or that human's body or body parts. We speak, for instance, of Saint Peter's bones under Saint Peter's - and they had better be Saint Peter's! It is the remains of Saint Peter's body.

But of course I can appreciate what you mean. To be properly or fully a human body would require the presence of a human soul united with that body and animating it; no shortage of logical absurdities would arise absent that, sort of like trying to define man's sexual act without the conditions necessary to realize fertilization or a natural child.

@ Luke

"Once a mind has embraced a logical contradiction, might that split it into two parts?"

But the mind cannot embrace a logical contradiction, strictly speaking, because such things are really non-things - again strictly. One at best things of different or contradictory things in turn; so I think of a square or I think of a circle - but a square circle cannot be thought, as there is no such thing or being to be thought.

> But the mind cannot embrace a logical contradiction, strictly speaking, because such things are really non-things - again strictly.

You'll have to elaborate on what you mean by "non-things", especially given WP: Category of being (unless you reject it?).

> One at best things of different or contradictory things in turn; so I think of a square or I think of a circle - but a square circle cannot be thought, as there is no such thing or being to be thought.

This threatens to merely presume that the mind cannot actually split into two. What do you do with the "double-minded man" in Ja 1:5–8? Reject it as something which cannot actually exist? But again, why? Perhaps your further explication of your first sentence will help; as it is, I do not understand it. Note that I do own Feser's The Last Superstition and Scholastic Metaphysics, although I've only read bits of the latter.

@Timocrates: "If I were to be cut in twain, the two bodies consequently produced would still be human."

Timocrates, if you go down to NAPA auto parts, what is in there is undoubtedly *auto* parts. But don't try to drive one of those parts home! Just because they are auto *parts* does not make them *autos*!

'Double-mindedness' is psychologically objective. the person could not be 'double-minded' in the first place if he were not conscious of an object through a formal self-consciousness via a simple subjectivity. Descartes et al are not saying that man lacks existential subjectivity (which would make him angelic), of which 'double-mindedness' is a necessary aspect. To continue to press existential conditions on the subject in order to contradict the subject's essential unity is something of a rhetorical exercise.

What I am saying or arguing is that there are certain things that are inconceivable because they are per se impossible - they are impossible beings. The thing cannot be conceived for its essence involves a contradiction, which makes the thing impossible.

Consider a man horse. What is it? In reality, it is nothing, because a man is not a horse and a horse is not a man. One would be thinking of something that has features or appearances of both perhaps a horse and a man; insofar as it is man, it cannot be horse; and insofar as it is horse, it cannot be man. But the combination would not make it properly human or properly a horse but something besides. This seems to be Aristotle's point when he discusses an alleged man-faced ox in his Physics.

Depending on what is meant by that, I can think of two ways a man could be said to be double-minded.

One would be when he desires ultimately contradictory ends, as having your cake and eating it too. That is physically impossible, but there is nothing impossible about enjoying cake endlessly, except extrinsically in consideration of many human and earthly limitations and realities (but not for God - God could produce cake ad infinitum for someone no problem and doubtlessly even make cake perfectly sufficient for his nutriment or make him impervious to any ill consequences).

Then there is contradiction or hypocrisy when we, e.g., violate our morals or beliefs. This seems most likely in the case of attempts to balance between temporal and eternal goods but where the temporal goods are exaggerated. And again this seems to be just a case of conflicting ends, perhaps motivated by fear or doubt where the sinner wrongly fears, say, death because he fears judgment so he sins to avoid what he fears would bring death. Or he overvalues himself imagining that he is better off alive for the Church or the world or the good of humanity or whatever or that he will just go to confession, which is presumptuous, or whatever. Now notice that his sinful acts remain morally impossible - he knows they are sins. Stealing or murder, for example, are by definition moral impossibilities - it is impossible to commit such an act morally. But they are of course not physically (extrinsically) impossible and certainly not per se (intrinsically) impossible acts. Theft or murder are sadly quite conceivable acts and very often - and even to an extent normatively - in man's power physically.

Now, let's say I want to be a saint but I want to be a sinner too. The problem is exactly in reconciling what is impossible. I have to, firstly, cease desiring to be a sinner if I wish to be a saint; and again, if I wish to be a sinner then I need to give up desiring to be a saint, as I simply cannot be both in reality. Being both is actually impossible ultimately; if it were, the serial killer who murders for thrill could be at the same time and even during the acts a saint and doing good works. But that is absurd.

Thanks for taking the time to really think through this. It definitely made me think through these matters more articulately—as Alasdair MacIntyre observes can happen with conflict, in Whose Justice? Which Rationality?. I continue to be amazed at how much of a genius MacIntyre is. Hopefully I can meet him before he passes into the next aiōn.

> And again this seems to be just a case of conflicting ends, [...]

I 100% disagree with the qualifier of "just". First, take a look at the word telos as used in Romans 10:4. I claim that it is a common telos which binds—a view Alasdair MacIntyre argues for in his momentous After Virtue (see his discussion of the polis). Furthermore, we have the following from another intellectual giant, Charles Taylor:

>> By contrast, the notion of self which connects it to our need for identity is meant to pick out this crucial feature of human agency, that we cannot do without some orientation to the good, that we each essentially are (i.e. define ourselves at least inter alia by) where we stand on this. What it is to be a self or person of this kind is difficult to conceive for certain strands of modern philosophy and above all for those which have become enshrined in mainstream psychology and social science. The self, even in this sense, ought to be an object of study like any other. (Sources of the Self, 33)

An "orientation to the good" is closely related to having a telos, if not identical. And so, I claim there is no more severe identity crisis than that of having multiple telē. If you want to absolutely destroy a person, one way is to force upon him or her multiple telē. It will be like a Procrustean bed which tears the person apart.

———

Now, suppose that this doesn't map onto the conception of the divisibility of the mind. Well, then I suspect that said model of the 'mind' is simply not one that is particularly useful for modeling reality! Can you show how this model you are defending accurately captures the above, as well as James' "double-minded man", in a way that is powerful, in a way that helps us bless other human beings and build them up, just as Jesus himself was a tektōn, a builder?

"An "orientation to the good" is closely related to having a telos, if not identical. And so, I claim there is no more severe identity crisis than that of having multiple telē. If you want to absolutely destroy a person, one way is to force upon him or her multiple telē. It will be like a Procrustean bed which tears the person apart."

And I don't disagree; however, it does not alter the fact that there are certain things because of our nature that simply cannot be done by us, and one such thing is conceiving of an intrinsically or per se impossible being. Hence that really is why someone's mind is as it were "doubled" - they are desiring (to use our example) in turn a square then a circle. But for all that he cannot conceive of a square circle let alone, poor fellow he would be, attempt to realize one in physical reality.

Indeed, this sort of thing taken too far can cripple a man exactly because the thing is impossible and one cannot act in keeping with the ends. Thus no doubt internal conflict must ultimately result.

Now, when Saint James speaks of the double-minded man, do you believe he is thinking of a man literally having two minds? Does the double-minded man says "my minds are telling me this and that"? That indeed would be quite remarkable, even possibly a boon; if I had two minds literally, then I expect I could multi-task with much greater ease, for instance. But there is nothing impossible about desiring contradictory things - I want to go to the park and enjoy the weather but I also want to go see a new movie only available in indoor theatres, say. This will result either in inaction or a choosing of one then another or one to the exclusion of the other.

Imagine that I have a perfect double. By that I mean a twin who has not only the same genetic structure, but also the PRECISE same ATOMIC structure, and the PRECISE same energy transfers going on between brain cells, and so on. According to materialism/reductionism, I would then have to exist twice. Would "I" have two different experiences?

It could be said that at the moment I got different stimuli picked up by my sensory organs, my "two brains" would diverge in structure (due to having to process different input) and there would instantly (or at least VERY QUICKLY) be two completely different people, or sense of "I".

But if I use that same logic, which seems sound, then the person I was 1/2 second ago could not have the same sense of "I that "I" currently have, and "I" should be very unstable. And yet here "I" am, consistently behaving and sensing different things every instant.

Is spiritual death, the sundering of flesh from spirit, perhaps model-able as the splitting of one mind into two? Live would come via reunion, via breaking down "the dividing wall of hostility" Paul speaks of in Eph 2.

A different way of looking at this is when Paul speaks of sin as having causal power over his body in Romans 7; is this not thinkable as there being a second mind which sometimes takes over his body? After all, he completely disassociates himself from this entity called 'sin': "it is no longer I who do it, but sin that dwells within me".

This speech of "indivisibility of mind" also strikes me as threatening to destroy the intelligibility of Paul's "but we have the mind of Christ" in 1 Cor 2:16.

———

Again, what I may be railing against is a bad model of the mind. Perhaps within that model, what you say is true. However, the picture of the thing is not the thing: Ceci n'est pas une pipe. So, does this model of the mind we're discussing capture reality well, or is it an approximation which might break down in the instances I am bringing up? Let's not idolize a model.

"Imagine that I have a perfect double. By that I mean a twin who has not only the same genetic structure, but also the PRECISE same ATOMIC structure, and the PRECISE same energy transfers going on between brain cells, and so on. According to materialism/reductionism, I would then have to exist twice. Would "I" have two different experiences?"

That is actually a very good point against materialism! The immediate, intuitive reaction of most people would be that they surely did not exist somehow twice; that their replica would not be themselves but another person, and this most readily and easily verified, for to be them they would also need to have an intellect and will proper and immediate to themselves; absent the capacity or natural constitution and orientation toward an 'I' and the possibility of freely making choices, the other wouldn't even be properly human. But they are supposed to be human. Therefore they have their own independent 'I' and will just as I do and, consequently, cannot be me.

And since Leonard Nimoy has sadly left us I think perhaps a Star Trek reference may be well in order. This is one problem with the idea of teleporters: in destroying or breaking down the individual, would that not have the consequence of killing the person? I think it would, however cool and useful teleportation would be because teleportation as it is in Star Trek destroys the person physically and then reproduces them. But this should kill them, meaning every teleportation would actually produce a new and different person or as it were replace them. However, for things not like us or living, materializing things or transporting them in that manner would not seem so problematic or potentially dangerous. How nice if I had a machine that on my command would make a cup of coffee! (Oh wait, I already do! Tassimo machine I love you! Lol).

"Is spiritual death, the sundering of flesh from spirit, perhaps model-able as the splitting of one mind into two?"

I think not.

Death in the natural order is a disheveling experience, which I think is in part why Aristotle - though his doctrine pointed to the immortality of the soul - doesn't seem to dwell long on this. For Aristotle, it seems, dying involved only loss and deprivation for ourselves in the natural order. I believe Professor Feser has given a number of very good blog posts about this explaining the thinking.

That being said, even Plato later on saw that there was reason to suspect that the soul would still naturally long for reunion with the body as being a soul that animates the body just was the nature of the human soul. For Aristotle this is perhaps even more so, as Aristotle did not share in Plato's contempt of bodily life and bodily goods.

I'm afraid I just don't understand how your model of the mind is helpful in understanding personhood whether the Bible's analysis thereof or just general experiences I've had in reality—including a lot of suicide prevention work. It might be a pretty model, but I just don't see how it actually matches reality to any good approximation. If anything, it accepts a level of individualism which is anti-Trinitarian, anti-imago Dei.

I think that would have to rest on your understanding of the mind. I am pretty certain the doctrine that I am expounding is in keeping with Saint Thomas's, whom I suspect would be the last person to deny the imago Dei.

Also, God really is three divine Persons. I am not really three persons or at least not in the way God is.

I am, to be sure, a son, a brother and if it's God's plan and will possibly also one day a father and husband to boot. In that way of seeing things, I can in a sense be many persons - but for all that, the problems I already mentioned with logical contradiction in my mind remain; in fact, if anything, the possibility for entertaining contradicting ends or desires is multiplied.

And there is of course the classical understanding we have in the Western or Latin tradition via Saint Augustine on how the individual human person is in the image of God that once more doesn't change the limitations of human nature or multiply the individual.

Indeed, on my reading of James 1:5-8 I think the doctrine there is perfectly in keeping with what I have so far said. The consequences of the double-mindedness is like what I said: he is unstable. But that is exactly because he desires contradictory ends: he desires good things from God but does not believe or have faith that God will provide him with those things. His faith is contradicted by his doubts and consequently he does not receive because he lacks faith.

"A different way of looking at this is when Paul speaks of sin as having causal power over his body in Romans 7; is this not thinkable as there being a second mind which sometimes takes over his body? After all, he completely disassociates himself from this entity called 'sin': "it is no longer I who do it, but sin that dwells within me".

This speech of "indivisibility of mind" also strikes me as threatening to destroy the intelligibility of Paul's "but we have the mind of Christ" in 1 Cor 2:16."

I wouldn't be too quick to endow sin with mind. Sin is like to nothingness or non-being; we therefore have less reason to endow it with being, especially being as mind which is a very good perfection of being. I would not want to be a mindless animal much less a lifeless rock, though arguably it is better to be a rock than not be at all.

That being said, I admit I do not have a ready answer for your objection here on that point.

As to the mind of Christ, here there is no difficulty I think, because we speak of men being like minded all the time. We can say people think like or in the spirit or tradition of someone already long dead - intellectual traditions attempt and often succeed in doing this all the time. But how much more for one who is still living and God to boot? Now if what the Apostle says is true - and of course I do believe it - then there must be nothing actually impossible about the Church having the mind of Christ; therefore, what the mind of Christ is, is manifest to the Church or in the Church; otherwise, this would not be real. But it is. Now I don't think that this implies that each Christian has two minds literally; his own and Christ's. Rather, I would think this means we have the mind of Christ by having a similar will and mind that is like to or in conformity with Christ's, and here we have unity and with that unity achieved we can speak of having the mind of Christ without caveat in common speech.

"So, does this model of the mind we're discussing capture reality well, or is it an approximation which might break down in the instances I am bringing up? Let's not idolize a model. "

But I find it best to keep in mind my own mind when discussing mind, as that is most evident to me. And I believe Professor Feser made some apt points about the problems of double-mindedness taken to far already in his post. In reality, possession would seem to be one case of being double-minded, but in the demonic this is definitely not a good thing and for all that there is a contradictory warring within the individual such that either the evil spirit or the person predominates over the person's body.

Now Christians are possessed by the Holy Spirit; however, this is of course radically different than demonic possession. The Holy Spirit brings joy, peace, gladness, comfort: the Holy Spirit strengthens and fulfills us. The Holy Spirit is not lordly or dominative as men or demons are, but gentle, peaceable and as it were quiet - not pushy or bossy but gently persuasive. The Holy Spirit is as a friend or guest, interiorly prompting us to do what is right and good and endowing us with the spiritual goods we need to do them, such as supplying courage even to martyrdom.

For all that, however, a Christian cannot conceive of a square circle, say, or realize contradictory ends, as these things are per se impossible. Hence when we see men in mental anguish it is often because they are entertaining contradictory goals, desires or aspirations for themselves that consequently frustrate them, the impossibility being a necessary imposition of reality (for you had asked what good this doctrine has for understanding people and reality).

Thank you though for this dialogue Luke and peace be with you in Christ!

On the materialism presupposed for your argument, I'm not sure it's possible for humans to have perfect doubles.

It could be said that at the moment I got different stimuli picked up by my sensory organs, my "two brains" would diverge in structure (due to having to process different input) and there would instantly (or at least VERY QUICKLY) be two completely different people, or sense of "I".

Suppose brain divergence does occur due to different stimuli. Since persons x and y are numerically non-identical to each other, it's impossible for them to at any point share identical spatiotemporal histories.

If x and y having different locations from each other is enough to cause these brain divergences, this means person x's brain could never at any moment be identical to person y's brain. So, if x and y having different locations from each other is enough to cause brain divergences (and, at least, I see no reason why it wouldn't), persons x and y are at every point in their histories qualitatively (as well as numerically) non-identical.

> I wouldn't be too quick to endow sin with mind. Sin is like to nothingness or non-being; we therefore have less reason to endow it with being, especially being as mind which is a very good perfection of being. I would not want to be a mindless animal much less a lifeless rock, though arguably it is better to be a rock than not be at all.

I am partial to Augustine's "Privation Theory of Evil", so your allusion to that is well-taken. But then we return to whether we even have a mind when we are enslaved to sin. What happened to the mind when Paul said, "I was once alive apart from the law, but when the commandment came, sin came alive and I died."? And what did he mean by "And you were dead in the trespasses and sins in which you once walked..."? What is it that happens to the mind when "God, being rich in mercy, because of the great love with which he loved us, even when we were dead in our trespasses, made us alive together with Christ—by grace you have been saved—and raised us up with him and seated us with him in the heavenly places in Christ Jesus..."?

On your model, what is killed by sin, what does law target, and what is raised from the dead? What is buried and raised with Christ?

> As to the mind of Christ, here there is no difficulty I think, because we speak of men being like minded all the time.

That seems like too shallow of a unity to account for e.g. Eph 4:1–7. The metaphor in the NT is that we are the body and Christ the head. This seems much more than "like minded":

>> ... the Head, from whom the whole body, nourished and knit together through its joints and ligaments, grows with a growth that is from God. (Col 1:19)

After all, surely there is a depth of unity in Mt 5:43–48, Jn 13:34–35, Jn 17:20–23 that transcends the kind of unity in the world? Isn't that what Jesus is getting at? So I'm really not happy with the phrase "like minded". It doesn't seem to capture the deep unity (and resultant glory) that the Trinity has, which we share in.

Exactly. But that also undermines materialism/reductionism, which holds that ONLY configurations of matter and energy are required to produce exactly MY sense of self. If what you are saying is true, then there MUST be some other factor beyond matter and energy (which are supposedly the only things that actually "exist") configurations which produce self. Again, I reject materialism (at least until such time as I have two simultaneous experiences).

If what you are saying is true, then there MUST be some other factor beyond matter and energy (which are supposedly the only things that actually "exist") configurations which produce self

Sorry, could you unpack this statement for me?

If you mean my "spatiotemporal histories" then, assuming the different locations cause brain divergences, I don't need there to be actual "historical properties" attached to a and b. As long as their different locations resulted in their having different brains, a and b would be qualitatively non-identical.

I think we are saying much the same thing. Two brains can't produce the same consciousness, regardless of matter/energy arrangements. There is such as thing as "uniqueness".

But that flies in the face of reductive materialism, which asserts that "self" is ONLY produced by arranging matter and energy into a very particular construction. And we're talking about only an average of about 5 pounds of mass per person.

Sometimes we are told that there are many universes in the multiverse and that therefore "we" exist in many of them. That can't be the case, since it would require EACH individual to be EXACTLY the same "I" or "ego". Since I am NOT having more than one sense of being, there either:

a. can't be a multiverse

and/or

b. can't be a material explanation of mind that reduces to only matter and energy. Something else is involved. I choose duality.

I'm not a materialist either, but I don't know of any version of materialism/reductionism according to which two down-to-the-atoms-identical "twins" would have literally and numerically the same consciousness. Even if it were the case that "self" was produced by an arrangement of matter, it wouldn't follow that a numerically different parcel of matter arranged in the same way would produce numerically the same "self." On the contrary, that the two parcels of matter were numerically different should imply, for the materialist, that the "selves" were too.

Well, what I wrote was that given a and b's different locations causes "brain divergences", they can't be the same. So, on the back of these divergences, I was denying that you can have persons that are at once numerically non-identical and qualitatively identical (because, given the divergences, their numerical non-identity entails their having at least slightly different brains).

Sometimes we are told that there are many universes in the multiverse and that therefore "we" exist in many of them. That can't be the case, since it would require EACH individual to be EXACTLY the same "I" or "ego". Since I am NOT having more than one sense of being, there either:

I don't want to go too far off-topic. But David Lewis's solution -- counterpart theory -- holds that, though each individual exists in only one world, it has counterparts in other worlds, where the counterpart relation is based on similarity but doesn't have the logic of identity.

Since he was a physicalistic reductionist about minds, I suppose that's in line with the reductionist answer to this transworld problem.

That is, to be clear, not only can't their brains be the same, but they can't ever be the same. There's no point at which they have the same brain and then it divergences. Their brains are just non-identical (both qualitatively and numerically).

What causes the mind, I wonder? If it's indivisible, does it spring forth whole from one glorious cause? I remember raising my sons. As most parents know, it's an amazing thing to watch their children's minds develop from scratch. That constant growth is coaxed by many bits and pieces of parental care. It should tell us minds are indeed composed of many parts, some of which are passed from generation to generation as a communal construction project. And if that fails to convince, our spouses will sometimes lament the pieces of our minds we lost somewhere along the way.

Ok . . . so let's go with the assumption that two otherwise perfectly identical individuals have completely different senses of self. This causes a much bigger problem for reductionism. It leaves a lack of explanation for sense of self. There is no way to explain what causes me to feel like "me".

Let me point something out that I was assuming, btw. Atoms (and therefore molecules) are not numbered. There is no "sequential identity" for atoms or the molecules they create (at least that has not been discovered). If that WERE the case, then I could be persuaded that two otherwise identical people (and I agree - that is so unlikely as to be "practically" impossible) could not have the same sense of self.

But since, as far as is currently known, atoms and molecules do not have anything that distinguished one from another, then there wouldn't be any way to create a consciousness with them in one construction that another (perfectly identical construction) wouldn't also produce. If the atoms and molecules ARE somehow "stamped" with some sort of individual identity, then they could.

Think of a DVD - if you imprint a certain pattern of 1s and 0s on it, you get the movie "Ground Hog Day". If you print the PRECISE pattern on a different disc, you do not get "Stripes".

If that WERE the case, then I could be persuaded that two otherwise identical people (and I agree - that is so unlikely as to be "practically" impossible) could not have the same sense of self.

It's not just unlikely. As I wrote, if different stimuli lead to different brains, it's impossible in a materialist universe. People are either born from parents or, possibly, grown in laboratories. However, they would have different stimuli by virtue of being numerically non-identical (which doesn't depend on the atoms being numbered, they're two distinct parcels of matter).

You originally mention brains diverging for this type of reason but, actually, I'm not unsympathetic to it. I've read naturalist accounts of actions altering brains, like Maddy's naturalistic account of how we develop a Goedel-like mathematical intuition.

But I've been wondering. Is such strict materialism even common amongst naturalists who are reductionists? I haven't read much mind-reductionist literature but, at least in other fields, I don't know of too many naturalists without at least some immaterial entities in their ontologies -- even if just properties, or something.

1. I do not think the mind dies when we die to sin in Christ; rather, it is perhaps transformed in a sense.

Again. In the sense that we receive a new mind in Christ I would not say this is any less or more mind than before, except again only in a sense of proper ends - we have a mind in keeping with what the human mind was and is meant for. It is also a mind, I would argue, much more conducive to true wisdom which is arguably the highest end of the human mind. All that the intellect desires to know seems to culminate in wisdom, as it is wisdom that makes man happy and facilitates for him the moral life. This is not to exclude divine enlightenment, trust in God or faithful awaiting for His guidance - a disposition to do these things would itself be a mark of wisdom.

2. I agree also that being like minded is not a satisfactory explanation or description for what Saint Paul said when he taught that the Church has the mind of Christ. Indeed, I ought to have remove that part as even as I wrote it I found it too weak, reflected, and leaned rather toward unity of mind with Christ. I would rather say unity of mind with Christ, our thoughts as it were being turned from vain and unholy things to things fruitful (especially for life and eternal life), holy and heavenly things, drawing our will to them also with God's help and grace.

"You could easily conceive of being rid of this second mind or self and carrying on “one and entire” without it, just as you can conceive of your “I” or ego carrying on “one and entire” in the absence of your arm or foot."

I have to disagree here and, in fact, in doing so I am strengthening the sense of an earlier point you made, which I found potentially problematic, that to, e.g., split a man in two would not result in two human bodies. And I think the solution is also going to present itself.

When I think about the proposition that should my arm be cut off I would continue whole and entire, my reaction to that in considering it is that I certainly would not feel one, whole or entire.

To give an example here. We all know that when someone who is beloved by another passes away or - even and especially in the thrall of say romantic love - just physically absent from the lover, then the person does not feel whole and entire but incomplete and sometimes deeply so. Similarly, should my arm be lopped off, I would certainly not feel whole and entire but even perhaps radically incomplete and not wholly or truly myself because my body is not complete. Such deficiencies may be less keenly felt by those who never enjoyed them in the first place, as a man born blind may not be so distraught as a man who has seen then been made blind. Or again in the sense of its having better to have loved and lost then never to have loved at all. Still, especially perhaps in the case of having not loved, objectively something is wanting to the human person. Of course, the lack is not itself sufficient to negate the "I" or ego or prevent the person from subsisting in being or existence; notwithstanding, there is something lacking.

Hence loving a proper body part does leave the human person somewhat incomplete, as most definitely the loss of the body entirely in death does.

And returning full circle, there is of course a sense that should a man be cut in half that both the resulting bodies are still both human (especially to that extent they remain alive or united with the person's soul); but, notwithstanding, the as this detracts from the proper end of the human or person's body, is it in some sense deficient and incomplete - or better, imperfect. So while an intact corpse is a human body, the lack of unity with the soul that animated the body makes it to that extent short of being a truly human body or a man's body full stop.

Jacquette’s reason for speaking of divisibility “into like parts” is that Descartes does not deny that we can distinguish different faculties within the mind, such as willing, perceiving, and conceiving.

But the fact is, each time the mind does any of these, the whole mind is basically doing it, barring dissociative states like hypnosis. Where the dissociation is of course a kind of illusion. And the whole mind is in a way in that illusion on both its sides, on the side of fooling and on the side of being fooled (except deeper states where only the latter remains).

About Me

I am a writer and philosopher living in Los Angeles. I teach philosophy at Pasadena City College. My primary academic research interests are in the philosophy of mind, moral and political philosophy, and philosophy of religion. I also write on politics, from a conservative point of view; and on religion, from a traditional Roman Catholic perspective.